Gamma Ray telescopes are the one mostly used by humans for majority of space observations.
Answer: Option A
Explanation:
Since the year 1965, Gamma ray telescopes have attained a major area in space research. As gamma rays are emitted by most of the astrophysical particles like novae, black holes, dwarf stars, supernovae, neutron stars, pulsars, so it is easy to find any changes in space. Even highly energetic gamma burst can also be observed by these telescopes.
So, among the other telescopes like radio, ultraviolet, visible light observations, gamma ray telescopes are mostly preferred for space observations. As the other telescopes have low range of observations and they may have losses. But gamma rays does not interact with other particles, there will be less chance of loss of signals for gamma observations.
Answer:
d
Explanation:
visible light observations
please is phisics basic ekekekekekeek
Answer:
B) [tex]R= \sqrt{(40N)^2+(30N)^2}[/tex]
Explanation:
Given [tex]\sum Fx=40N\ \ \ \ \ \ \ \ \ \sum Fy=30N[/tex]
As the forces are on X and Y-axis. We can see the angle between the forces is 90°
Using vector addition formula. Since the angle between the forces is 90°
[tex]R=\sqrt{\sum (Fx)^2+\sum (Fy)^2}[/tex]
[tex]R= \sqrt{(40N)^2+(30N)^2}[/tex]
Please see the attachment.
All leukocytes fight off infections by using phagocytosis.
A.
True
B.
False
the question is correct
What is an example of light energy converted into electrical energy?
(Help, I have my exam in 1 day)
Answer:
Solar panel
Explanation:
You can often find solar panels on top of rooftops of buildings or apartments (usually in less developed countries), as because it consumes the light energy from sunlight and converts it into electrical energy which can be later used to run electrical energy in that specific building.
What is the law of superposition. Please explain
Answer:
THE LAW OR PRINCIPLE OF SUPERPOSITION; States that when two identical waves are brought, the resultant disturbance is the algebraic sum of the individual disturbances of the two waves.
Explanation:
Most stationary waves are obtained as a result of the combination or superposition of an incident wave and it's reflected wave. Like in music, they result from the stationary waves of plucked strings leading to the Superposition law.
Peace.
Answer: It is the way you can date layers of rocks, sediment and fossils. The most recent layer is the youngest in geologic time, while the bottom layer is always the oldest.
Explanation:
a basic law of geochronology, stating that when there is any undisturbed sequence of rocks deposited in layers, the youngest layer is on top and the oldest on bottom, each layer being younger than the one beneath it and older than the one above it.
If humans evolved from apes or chimps, why are the chimps and apes still here?
Answer:
Chimps and apes are still here because humans did not evolve from all apes and chimps.
Explanation:
To measure the mass of a planet with the same radius as Earth, an astronaut drops an object
from rest (relative to the planet) from an altitude of one radius above the surface. When the
object hits its speed is 4 times what it would be if the same experiment were carried out for
Earth. In units of Earth masses, the mass of the planet is:
A. 2
B. 4
C. 8
D. 16
E. 32
ans: D
Answer:
D. 16
Explanation:
For this you must the gravitational force equation, i.e.
[tex]\mathbf{F = \frac{Gm_{1}m_{2}}{r^{2}}}[/tex]
where [tex]\textrm{m}_{1}[/tex] and [tex]\textrm{m}_{2}[/tex] are mass of objects,
[tex]\textrm{r}[/tex] is the distance between objects
and [tex]\textrm{G}[/tex] is the universal gravitational constant which is approximately equal to [tex]\mathrm{6.67\times10^{-11} \frac{m^3}{kg\cdot s^{2}}}[/tex].
You must know that energy and its conservation in terms of gravitational forces.
Let mass of earth be equal to M and radius of earth as R.
Potential energy of an object of mass m at a distance r from center of earth = [tex]\mathbf{PE = -\frac{GMm}{r}}[/tex]
Kinetic energy of same object at any point of time = [tex]\mathbf{KE = \frac{1}{2}mv^{2}}[/tex] where v is the speed of the object.
Energy conservation states that total energy of a system is always constant.
Total energy = Potential energy + Kinetic energy
∴ Total energy initial = Total energy final
let the mass of object be m and mass of planet be [tex]\mathbf{M_{p}}[/tex] and initial distance between object and center of plant is equal to 2R. let the speed of object of object on earth equal to v.
Initial Kinetic energy is zero(0) as it is at rest so its speed is zero.
Total energy initially on earth= [tex]\mathrm{-\frac{GMm}{(2R)^{2}}+0}[/tex]
Total energy initially on planet= [tex]\mathrm{-\frac{GM_{p}m}{(2R)^{2}}+0}[/tex]
Total Energy finally on earth = [tex]\mathrm{-\frac{GMm}{R^{2}}+\frac{1}{2}mv^{2}}[/tex]
Total Energy finally on planet = [tex]\mathrm{-\frac{GM_{p}m}{R^{2}}+\frac{1}{2}m(4v)^{2}}[/tex]
Solving equation of earth
[tex]\mathrm{-\frac{GMm}{(2R)^{2}}+0=-\frac{GMm}{R^{2}}+\frac{1}{2}mv^{2}}[/tex]
[tex]\mathrm{-\frac{GMm}{4R^{2}}=-\frac{GMm}{R^{2}}+\frac{1}{2}mv^{2}}[/tex]
[tex]\mathrm{\frac{GMm}{R^{2}}-\frac{GMm}{4R^{2}}=\frac{1}{2}mv^{2}}[/tex]
[tex]\mathrm{\frac{3GMm}{4R^{2}}=\frac{1}{2}mv^{2}}[/tex]
[tex]\mathrm{\frac{3GM}{2R^{2}}=v^{2}}[/tex]
[tex]\therefore\mathbf{v^{2}=\frac{3GM}{2R^{2}}}[/tex] _________eq(1)
Solving equation of planet
[tex]\mathrm{-\frac{GM_{p}m}{(2R)^{2}}+0=-\frac{GM_{p}m}{R^{2}}+\frac{1}{2}m(4v)^{2}}[/tex]
[tex]\mathrm{-\frac{GM_{p}m}{4R^{2}}=-\frac{GM_{p}m}{R^{2}}+\frac{16}{2}mv^{2}}[/tex]
[tex]\mathrm{\frac{GM_{p}m}{R^{2}}-\frac{GM_{p}m}{4R^{2}}=8mv^{2}}[/tex]
[tex]\mathrm{\frac{3GM_{p}m}{4R^{2}}=8mv^{2}}[/tex]
[tex]\mathrm{\frac{3GM_{p}}{32R^{2}}=v^{2}}[/tex]
[tex]\therefore\mathbf{v^{2}=\frac{3GM_{p}}{32R^{2}}}[/tex] ___________eq(2)
Using eq(1) and eq(2)
[tex]\mathrm{\frac{3GM_{p}}{32R^{2}}=\frac{3GM}{2R^{2}}}[/tex]
[tex]\mathrm{\frac{M_{p}}{16}=M}[/tex]
[tex]\therefore\mathbf{M_{p}=16M}[/tex]
Therefore mass of planet is 16 times the mass of Earth.
The mass of the planet is 16 times that of Earth. This is calculated based on the speed of a dropped object on the planet compared to Earth, which indicates its gravity and mass.
Explanation:The speed of a dropped object on another planet is determined by the acceleration due to gravity on that planet, which is influenced by the planet's mass. If the speed of the object upon arriving at the ground is four times greater on this planet vs. Earth, that indicates that the gravity (and thus the mass) of this planet is 16 times that of Earth. Therefore, in units of Earth masses, the mass of the planet is 16.
To further elucidate, the speed of the object when it hits the ground is proportional to the square root of the mass of the planet. Thus, if the speed is 4 times higher than what it would be on Earth, the mass of the planet must be 4^2, or 16 times the mass of Earth. Hence, the correct option is D. 16.
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an electromagnetic wave has a frequency of 6.0 x 10^18 Hz. What is the wavelength of the wave?
Answer:
500 nm
Explanation:
[tex]\lambda = c/\nu = \frac{3*10^8}{6*10^{18}} = 5*10^{-11}[/tex] m
Answer:
5*10^-11
Explanation:
From alvs
What is AC concerning electricity?
Answer:
Alternating current
Explanation:
The electrical current periodically changes direction.
Answer:
alternating current
Explanation:
A stands for alternating
C stands for current
the current which changes direction ( several times per second ) is known as AC or alternating current
How do I do number 8, plz respond quick, I have a big unit test on this and I’m rocking a 65 science average rn. Thank you for the help
Answer:
3 is the correct answer for number 8
Number three is the one. The same lines are there but they're all shifted toward the red end. They all show up at longer wavelengths than they should. That suggests that the distant Galaxy he's observing is speeding away from us.
Which formula correctly expresses the property density?
Question 7 options:
(A) D = m/v
(B) D = m*v
(C) D = v + m
(D) D = v/m
Answer:
Option A
D = m/v
Explanation:
Density is defined as mass per unit volume of an object. Therefore, D=m/v where m is the mass of the object and v is the volume
Therefore, option A is the right option
SP: Calculate the moment
exerted with the claw hammer if
the person exerts a force of 80N
and distance equals 25cm. Give
the unit
Answer:
Moment of the force is 20 N-m.
Explanation:
Given:
Force exerted by the person is, [tex]F=80\ N[/tex]
Distance of application of force from the point about which moment is needed is, [tex]d=25\ cm=\frac{25}{100}\ m=0.25\ m[/tex]
Now, we know that, moment of a force 'F' about a point at a perpendicular distance of 'd' from the same point is given as the product of the force and the perpendicular distance.
Therefore, the moment of the force about the end of the claw hammer is given as:
[tex]M=F\times d\\\\M=(80\ N)(0.25\ m)\\\\M=20\textrm{ N-m}[/tex]
Hence, the moment of the force exerted by the person about the end of the claw hammer is 20 N-m.
The required value of moment of force exerted on the claw hammer is of 20 N-m.
Given data:
The magnitude of force exerted by hammer is, F = 80 N.
The distance covered due to applied force is, s = 25 cm = 0.25 m.
The moment of force is termed as the turning effect produced by the applied force. In other words, moment is a term used to measure the tendency of linear force to rotate any object. The mathematical expression for the turning moment is given as,
M = F × s
Solving as,
M = 80 × 0.25
M = 20 N-m
Thus, we can conclude that the required value of moment of force exerted on the claw hammer is of 20 N-m.
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When a pitcher throws a baseball, it reaches a top speed of 45 m/s. If the
baseball takes 0.9 seconds to travel from the pitcher to the catcher, what is
its acceleration? (Assume the ball is moving at 0 m/s right before it leaves
the pitcher's hand.)
A. 45 m/s2
B. 50 m/s2
C. 55m/s 2
D. 40 m/s2
Answer:
B. 50 m/s²
Explanation:
Given:
Initial velocity of the ball is, [tex]u=0\ m/s[/tex]
Final velocity of the ball is, [tex]v=45\ m/s[/tex]
Time taken by the ball is, [tex]t=0.9\ s[/tex]
Acceleration is defined as the rate of change of velocity. So, the velocity of the ball is changing with time. So, acceleration is given as:
[tex]a=\frac{v-u}{t}[/tex]
Plug in 0 for 'u', 45 for 'v', 0.9 for 't' and solve for acceleration, 'a'. This gives,
[tex]a=\frac{45-0}{0.9}\\\\a=\frac{45}{0.9}\\\\a=50\ m/s^2[/tex]
Therefore, the acceleration of the ball is 50 m/s².
This type of burn results from high temperatures caused by an electric arc or explosion near the body
Answer:
The arc and flash burns results from high temperatures caused by an electric arc or explosion near the body
Explanation:
The arc and flash burn occurs due to high temperature because of electric arc or explosion near the body. The basic reason for catching of fire is due to clothing. Because the fact the fabric catches fire more easily. For less damage the first thing one must follow is application of the antibiotic ointment as well as dressing soon. In severe cases it requires surgery. when electricity passes through our body causes burning very rapidly.
Final answer:
An electrical burn occurs when the skin is exposed to high temperatures from an electric arc or explosion, which can lead to serious complications, including dehydration, electrolyte imbalance, and infection. Immediate medical attention and treatment with IV fluids and nutrients are critical.
Explanation:
The type of burn described results from high temperatures caused by an electric arc or explosion near the body, which is often referred to as an electrical burn. These burns occur when the skin is damaged by intense heat from an electric source and can be extremely dangerous. They can be fatal due to the death of skin cells, leading to massive fluid loss, dehydration, electrolyte imbalance, and potential renal and circulatory failure.
Such burns require immediate medical treatment, which includes administering intravenous fluids to combat dehydration and providing intravenous nutrients to help the body repair tissues and replace lost proteins. Moreover, electrical burns increase the risk of infection as the damaged skin is more vulnerable to bacteria and pathogens.
In Which figure below is the trend line drawn correctly
Answer:
The first graph is the trend line.
Explanation:
Trend Line
It's a line indicating the tendency of something being measured or evaluated. The trend line is meant to represent an approximation of a set of points of a measured magnitude.
We have three possible 'trend lines' to choose from. The second is not a line, so it's not the correct option. The third is not a line either, it's just a graph who joins all the measured points. It doesn't mark a trend.
The first graph is a trend line because it's a single line and can be used to represent the whole set of values .
how much force is acting on a 150g object in free fall
Answer:
The force acting on the free-falling object is, F = 1.47 N
Explanation:
Given data,
The mass of the object, m = 150 g
When an object is under free-fall, the only force acting on the object is the gravitation force neglecting the air resistance.
So, when an object is close to the surface of the earth acceleration due to gravity acting on the object is equal to g.
The value of g at the surface of the Earth is, g = 9.8 m/s²
Therefore, the force acting on the object under free fall is,
F = mg
= 0.15 x 9.8
= 1.47 N
Hence, the force acting on the free-falling object is, F = 1.47 N
20. A photographer takes an average of 15 pictures per session. The total
number of pictures pes) is a function of the number of sessions
a. Identify the independent and dependent variables.
b. What values of the domain and range make sense for this situation?
Explain.
c. Write a function to represent the total number of pictures taken. Then
determine the number of pictures taken in 22 sessions.
Answer:
A)
Independent variable -> number of sessionsDependent variable -> number of picturesB)
Values of the domain that make sense would be those from 0 on because there are no negative number of sessions; values of range that make sense would be also those from 0 on because there are no negative number of pictures.
C)
[tex]f(x)=15x[/tex], where "x" is the number of sessions.
If we have 22 session then:
[tex]f(22)=15*22[/tex]; f(22)=[tex]f(22)=330[/tex]
Explanation:
What is the difference between a horizontal line on a position graph and a horizontal line on a speed graph.
-- A horizontal line on a position/time graph says that as time goes on, the position isn't changing. The object is standing still. At rest. Motionless.
-- A horizontal line on a speed/time graph says that as time goes on, the speed isn't changing. If that doesn't happen to be zero, then the object is moving at a constant speed, and its position keeps changing at constant rate. On a position/time graph, this same motion would be a straight line slanting upward.
Final answer:
A horizontal line on a position vs. time graph indicates an object at rest, while a horizontal line on a speed vs. time graph shows an object moving at a constant speed.
Explanation:
Graphs play an essential role in analyzing motion in physics. The representation of motion on position vs. time graphs and speed vs. time graphs can tell us a lot about the behavior of moving objects.
When examining a position vs. time graph, a horizontal line indicates that the position of an object does not change as time passes, which means the object is stationary or at rest. There is no change in position, so the velocity is zero. On the other hand, a horizontal line on a speed vs. time graph suggests that the object is moving at a constant speed. The flat line indicates that the speed does not change over time; the object is not accelerating or decelerating.
To sum up, a horizontal line on a position graph signifies no movement (zero velocity), while a horizontal line on a speed graph indicates constant movement (constant speed).
Final answer:
A horizontal line on a position vs. time graph indicates an object at rest, while a horizontal line on a speed vs. time graph shows an object moving at a constant speed.
Explanation:
Graphs play an essential role in analyzing motion in physics. The representation of motion on position vs. time graphs and speed vs. time graphs can tell us a lot about the behavior of moving objects.
When examining a position vs. time graph, a horizontal line indicates that the position of an object does not change as time passes, which means the object is stationary or at rest. There is no change in position, so the velocity is zero. On the other hand, a horizontal line on a speed vs. time graph suggests that the object is moving at a constant speed. The flat line indicates that the speed does not change over time; the object is not accelerating or decelerating.
To sum up, a horizontal line on a position graph signifies no movement (zero velocity), while a horizontal line on a speed graph indicates constant movement (constant speed).
What is the distance between the earth and the sun?
Answer:
an average of 92,955,807 miles
Explanation:
Answer:
149,600,000 kilometers (km) or 92,900,000 miles.First I should say that the Earth's orbit around the Sun is elliptical, not perfectly circular, so the Earth-Sun distance is changing as we speak just from the Earth traveling in its orbit around the Sun. There are some long-period oscillations, but those are very small, and don't imply that we're systematically moving towards or away from the Sun.
I hope this answer helps you :)
Two water balloons of mass 0.35 kg collide and bounce off of each other
without breaking. Before the collision, one water balloon moved at a velocity
of 2.5 m/s east, while the other moved at a velocity of 2.25 m/s west. After
the collision, one balloon moves at a velocity of 1.75 m/s west. What is the
velocity of the other water balloon?
O
A. 2 m/s west
O
B. 0.25 m/s east
O
C. 0.25 m/s west
O
D. 2 m/s east
Answer:
Option D
2 m/s East
Explanation:
From the law of conservation of momentum, the sum of initial momentum equals the sum of final momentum
Momentum, p=mv where m is the mass and v is the velocity
Since the masses are the same then
[tex]m(u_1+u_2)=m(v_1+v_2)[/tex]
Therefore
[tex]u_1+u_2=v_1+v_2[/tex]
where [tex]v_1[/tex] and [tex]v_2[/tex] are final velocities of objects while [tex]u_1[/tex] and [tex]u_2[/tex] are the initial velocities respectively
Taking East direction as positive then West as negative and by substitution
[tex]2.5+-2.25=v_1-1.75[/tex]
Therefore
[tex]v_1=2 m/s[/tex] hence East since it's positive
Answer:
2 m/s east
just did it ;D
Explanation:
if the Moon were twice as big, _______. A) its pattern of apparent shapes would probably be the same B) its pattern of apparent shapes would probably be reversed C) it probably would no longer revolve around Earth D) it would probably revolve in the opposite direction
(Sorry if the subject is wrong)
If the Moon were twice as big, its pattern of apparent shapes would be probably be reversed.
Option B
Explanation :The motion or the movement of the earth and that of the moon trajectory are the same of one another. There are many reasons for the great differences in the earth and the space. But the gravity plays a very major and an important role in controlling all the activities of these celestial bodies.
The projectile motion plays a very important and a crucial role. It is plays were the parabolic motions and the paths come into act. They also move in a definite speed in order to control the movement.
Find the current i in:
Answer:
I = 24 A
Explanation:
This is Parallel Circuit and it is the first principle of parallel circuit that voltage will be equal in all components in the circuit
It includes 10 resistors Therefore the voltage across,
R1 = R2 = R3 = R4 = R5 = R6 = R7 = R8 = R9 = R10 = voltage in battery
Ohm's LawWe will apply Ohm's Law to each resistor to find its current because we know the voltage across each resistor is 12 V and the resistance of each resistor is 5Ω
I (R1) = E (R1) / R1
I (R1) = 12v / 5Ω
I (R1) = 2.4 A
The value resistance E of all resistors are same therefore by applying the formula above the value of current in all resistors will be 2.4 A
The Total current in the circuit will be
I (total) = I (1) + I (2) + I (3) + I (4) + I (5) + I (6) + I (7) + I (8) + I (9) + I (10)
I (total) = 2.4 + 2.4 + 2.4 + 2.4 + 2.4 + 2.4 + 2.4 + 2.4 + 2.4 + 2.4
I (total) = 24 A
2) If two locations have the same latitude and are on a coast, what factor determines the air temperature
Ocean Currents is the factor that determines the air temperature in coastal regions having same latitude.
Explanation:
There are factors that use to determine air temperature. They are latitude, altitude, region, water current, etc and it is based on the combination of water, air, and land.
If two coastal regions situated in the same latitude means they are not in the same region. Another city can be in the same latitude but in longitude. All the coastal regions don't have the same air temperature.
The air temperature in coastal regions can measured by the Ocean Current. A hypothesis of using cold water and warm water use to determine the air temperature.
what is friction? (explain if full sentences)
Answer: what comes to mind when we hear the word "Friction" ?
Basically friction is a "Force" that opposes an intend(ing) motion.
Explanation:
By motion I mean movement.
By force I mean a body that carries with it energy.
So to understand this better, just see it as a force(thing) that prevents or stops you from taking action.
What force causes the periodic motion of a pendulum?
O
A. Gravity
O
O
O
B. Elastic force
C. Nuclear force
D. Electric force
Answer:
the Answer is A
Explanation:
because the swinging motion of a pendulum is due to the force of gravity generated by the earth's size
How much force does an object with mass of 100 kg need to accelerate at 18 m/s2
A coil of wire, a battery, a few paper clips, and a thermometer are on a table of supplies
What other material or materials would be needed for a student to construct a basic electric motor?
A)A magnet
B)Some tape
C)An electric generator
D)Alligator clips and a plastic cup
The other material would be needed for a student to construct a basic electric motor is a magnet.
Answer: Option A
Explanation:
For constructing fundamental electric motors coils of wire, the battery, few paper clips, a thermometer, and a magnet are mandatory. The principle on which it works is when in magnetic field rectangular coil placed and current passes than force will act on it and rotate it continuously to convert electrical energy into mechanical energy.
Here magnet is compulsory to generate motion when two bar magnets placed against the north and south pole of each other than attractive force but if placed in a similar direction than repulsive force occur. Therefore, these attractive and opposing forces generate rotational motion.
Answer:
The answer is A
Explanation:This is the answer
f a light bulb produces 60.0 J of electrical energy and is 45% efficient, how much energy does it use?
a)133 J
b)1.33 J
c)0.75 J
d)2700 J
Answer:
133 j
Explanation:
We are able to see an object when it:
A. is between our eyes and a light source.
B. emits infrared (heat) radiation.
C. reflects one or more visible light frequencies.
D. emits one or more visible light frequencies.
Answer:
C. reflects one or more visible light frequencies.
Explanation:
The color that we see is the color that is deflected from the RGBHSB.etc. This means that the light has all the colors within, and the object it hits absorbs all but one color, in which it deflects for our eyes to see.
~
We get hurt when we jump on a muddy floor than on a hard floor. give reason
A muddy floor can be very slippery so if you jump on a muddy floor, you will most likely slip and hurt yourself.
A hard floor will most likely be dry. So when you jump on a hardwood floor, you are less likely to slip. But, you can hurt your knees if you're not careful.
Answer:
Injury can occur
Explanation:
you might be running then you start jumping without putting your heels down, then might get achilles tendonitis in your achilles tendons.
1. Calculate the new gravitational force between A and B if the mass of object A is doubled and distance R doubles
2.Calculate the new gravitational force between A and B if the mass of object A is halved and distance R doubles.
1) The new gravitational force is half of the original force
2) The new gravitational force is 1/8 of the original force
Explanation:
1)
Let's call F the initial gravitational force between the object A and B. The magnitude of F is given by the equation
The magnitude of the gravitational force between two objects is given by
[tex]F=G\frac{m_A m_B}{R^2}[/tex]
where
[tex]G=6.67\cdot 10^{-11} m^3 kg^{-1}s^{-2}[/tex] is the gravitational constant
[tex]m_A,m_B[/tex] are the masses of the two objects
R is the separation between them
In this part of the problem, we are told that the distance between the two objects doubles, so the new distance is
R' = 2R
While the mass of object A is doubled, so the new mass is
[tex]m_A' = 2m_A[/tex]
Therefore, the new gravitational force is
[tex]F' = \frac{Gm_A' m_B}{R'^2}= \frac{G(2m_A) m_B}{(2R)^2}=\frac{1}{2}(\frac{Gm_A m_B}{R^2})=\frac{F}{2}[/tex]
Therefore, the new force is half of the original force.
2)
In this second part of the problem, the distance between the two objects doubles, so the new distance is
R' = 2R
While the mass of object A is halved, so the new mass is
[tex]m_A' = \frac{m_A}{2}[/tex]
Therefore, the new gravitational force this time is:
[tex]F' = \frac{Gm_A' m_B}{R'^2}= \frac{G(m_A/2) m_B}{(2R)^2}=\frac{1}{8}(\frac{Gm_A m_B}{R^2})=\frac{F}{8}[/tex]
Therefore, the new force is 1/8 of the original force.
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